Unverified Commit 35c9701e authored by Christian Brauner's avatar Christian Brauner
Browse files

exit: move wake_up_all() pidfd waiters into __unhash_process() 

Move the pidfd notification out of __change_pid() and into
__unhash_process(). The only valid call to __change_pid() with a NULL
argument and PIDTYPE_PID is from __unhash_process(). This is a lot more
obvious than calling it from __change_pid().

Link: https://lore.kernel.org/20250411-work-pidfs-enoent-v2-1-60b2d3bb545f@kernel.org


Reviewed-by: default avatarOleg Nesterov <oleg@redhat.com>
Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parent 1e940fff

kernel/exit.c

+5 −0
Original line number Diff line number Diff line
@@ -133,8 +133,13 @@ struct release_task_post { 
static void __unhash_process(struct release_task_post *post, struct task_struct *p,

			     bool group_dead)

{

	struct pid *pid = task_pid(p);



	nr_threads--;



	detach_pid(post->pids, p, PIDTYPE_PID);

	wake_up_all(&pid->wait_pidfd);



	if (group_dead) {

		detach_pid(post->pids, p, PIDTYPE_TGID);

		detach_pid(post->pids, p, PIDTYPE_PGID);

kernel/pid.c

+0 −5
Original line number Diff line number Diff line
@@ -359,11 +359,6 @@ static void __change_pid(struct pid **pids, struct task_struct *task, 
	hlist_del_rcu(&task->pid_links[type]);

	*pid_ptr = new;



	if (type == PIDTYPE_PID) {

		WARN_ON_ONCE(pid_has_task(pid, PIDTYPE_PID));

		wake_up_all(&pid->wait_pidfd);

	}



	for (tmp = PIDTYPE_MAX; --tmp >= 0; )

		if (pid_has_task(pid, tmp))

			return;